Positive is positive. It was just faint because you are just now missing your cycle. But I would say you are DEFINITELY pregnant. I have never had a test come back positive when I was not pregnant or vice versa.
Yes, faint or dark...if the line is present that means you are pregnant. However, I would test again in a few days just to confirm that. And follow up with your doctor for a blood test to be certain and for prenatal care. There have been instance of false positives, but they are extremely rare. I have always heard that you can get a false negative, but never a false positive.
I meant to say Congrats :)
Faint positive means pregnant! Good luck,!